Extractive probe/TDLAS measurements of acetylene in atmospheric-pressure fuel-rich premixed methane/air flames

摘要

One of the key intermediates in many high-temperature processes is acetylene (C_2H_2), which plays an important role in the formation of polycyclic aromatic hydrocarbons and soot in hydrocarbon combustion, and in the chemical vapor deposition of diamond. Acetylene has been extensively investigated in both atmospheric- and low-pressure flat premixed flames. At atmospheric pressure, large discrepancies have been observed between measured results and those calculated based on the C_2H_2 submechanism derived from Miller and Melius. Moreover, calculations performed in [11] using the rate constant for the reaction C_2H_2 + OH = C_2HCO + H adopted from the measurements in propane/air flames, which is 10 times larger than that recommended by Miller and Melius, still overpredicted the measured postflame acetylene concentrations in methane/air flames. This discrepancy prompted the authors of [11] to recommend further validation of the acetylene mechanism.